Data in one table can be replicated to another table that is in the same cluster or in a separate cluster. This type of
replication is in addition to the automatic replication that occurs with table regions within a volume.

MapR-DB is an enterprise-grade, high performance, NoSQL (“Not Only SQL”) database management system. It is used to add
real-time, operational analytics capabilities to big data applications. As a multi-model NoSQL database, it supports both
JSON document models and wide column data models.

MapR-DB can be used as both a document database and a wide-column database. As a document database, OJAI documents are
stored in MapR-DB JSON table. As a wide-column database, binary files are in stored MapR-DB binary tables.

Data in one table can be replicated to another table that is in the same cluster or in a separate cluster. This type of
replication is in addition to the automatic replication that occurs with table regions within a volume.

In MapR-DB table replication, MapR-DB replicates updates to tables (binary and JSON) on source MapR clusters to
replicas of those tables on destination MapR clusters. Gateways are services that receive these updates and apply
them to the replicas.

When you index MapR-DB tables in Elasticsearch, MapR-DB replicates table updates to corresponding Elasticsearch types.
The MapR-DB tables are in MapR clusters, and the types are in Elasticsearch clusters. Gateways receive table updates
and pass them to nodes in Elasticsearch clusters.

The MapR Sandbox for Hadoop is a fully-functional single-node cluster that gently introduces business analysts, current
and aspiring Hadoop developers, and administrators (database, system, and Hadoop) to the big data promises of Hadoop and
its ecosystem.

These release notes contain information about Version 5.2 of the MapR Converged Data Platform.

Table Replication

Data in one table can be replicated to another table that is in the same cluster or in
a separate cluster. This type of replication is in addition to the automatic replication that
occurs with table regions within a volume.

Note: MapR binary tables can only be replicated to binary tables; MapR JSON tables can only be replicated to JSON tables.

Tables that data is replicated from are called source tables, while tables that
data is replicated to are called replicas.

Clusters that data is replicated from are called source clusters. Clusters that
data is replicated to are called destination clusters. A single cluster can be both a source
cluster and a destination cluster, depending on the replication configuration in which the
cluster participates.

Replication takes place between source and destination clusters. However, source
clusters do not send data to nodes in the destination cluster directly. The replication stream
(the data being pushed to the replicas) is consumed by one or more MapR gateways in the
destination cluster. The gateways receive the updates from the source cluster, batch them, and
apply them to the replica tables. Multiple gateways serve the purpose of both load balancing
and failover.

Gateways for Replicating MapR-DB Tables
In MapR-DB table replication, MapR-DB replicates updates to tables (binary and JSON) on source MapR clusters to replicas of those tables on destination MapR clusters. Gateways are services that receive these updates and apply them to the replicas.

Gateways for Indexing MapR-DB Data in Elasticsearch
When you index MapR-DB tables in Elasticsearch, MapR-DB replicates table updates to corresponding Elasticsearch types. The MapR-DB tables are in MapR clusters, and the types are in Elasticsearch clusters. Gateways receive table updates and pass them to nodes in Elasticsearch clusters.